Final answer:
The source of origin is not a standard classification for drugs, which are instead commonly categorized by therapeutic action, physiologic action, and affected body system.
Step-by-step explanation:
The classfication of drugs does not typically include the source of origin as a standard category. Drugs are commonly classified based on their therapeutic action (what they are used to treat), their physiologic action (how they influence body functions), and the affected body system (the part of the body they act upon). For instance, understanding the therapeutic action can assist in determining the drugs that can rectify a disease, the symptoms of the disease, and its severity. In contrast, knowing a drug's physiologic action can help one to understand its mode of action, which refers to the ability of an antimicrobial drug to harm the target microbe without harming the host. Lastly, examining the affected body system can reveal the ancestry and genetic origin of diseases and their susceptibility to various drugs.